Predecessor, tell me about your P1 as that is the one I have interest in at this time.
PROS:
P1 is a tight little number. First thing you notice are the ergonomics. I personally like the feel of it in the hand over the P99AS/PPQ/VP9/320 group - not taking away anything from the ergos of any of these guns, just letting you know what crowd the P1 fits in with when you put it in your hand.
It has a great single action trigger pull that is short, crisp and clean (as is the hallmark of the GP pistols) - the reset is absolutely bonkers and is even shorter than the reset on the X-Calibur.
But this is a carry gun for me and the impressive piece of the trigger is it's double action pull. It is light (for a DA) smooth and intuitive. My favorite DA pull of any gun in it's class.
Recoil is a breeze as with the other GP pistols.
CONS:
The lines on the P1 are a little sharp for me. For carry, I prefer the rounded and smoothed lines of the P45.
The mags are not marked. Not a huge deal but it's an extra touch that would be appreciated to know the capacity of the mags.
Takedown is a little odd - I have an MK 7 that has the takedown cog built into the trigger guard so you begin like a PPK - and continue in that vein by removing the slide rearward. With a non-fixed barreled pistol I forget to put the slide back on from the rear so it takes a bit of getting used to but in no way affects the performance of the gun